Latest / History of the Universe Physics & Electricity Vol. 3 / 028 - Electricity - Chapter 9 - Electric Railways

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028 - Electricity - Chapter 9 - Electric Railways · History of the Universe Physics & Electricity Vol. 3

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Speaker 1: Section twenty eight of the Science History of the Universe,
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Speaker 1: Volume three. This is a liprivox recording. All the privox
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Speaker 1: recordings are in the public domain. For more information or
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Speaker 1: to volunteer, please visit liprivox dot org. Recording by Avay
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Speaker 1: in August two thousand sixteen, The Science History of the Universe,
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Speaker 1: Volume three, edited by Francis rold Wheeler. Electricity, Chapter nine
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Speaker 1: electric railways. Although the earliest recorded experiments date back three
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Speaker 1: quarters of a century, the electric railway is essentially of
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Speaker 1: modern development, for it achieved the recognized position less than
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Speaker 1: twenty years ago, long after the telephone, the arc and
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Speaker 1: incandescent lamp, and the stationary electric motor had been thoroughly established.
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Speaker 1: This is but natural, for it is the law logical
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Speaker 1: outcome of the establishment of certain cardinal principles and practices
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Speaker 1: in the kindred arts. The first roads to carry passengers
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Speaker 1: commercially were built in Europe, but the first railway experiments
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Speaker 1: and the modern commercial impetus, as well as most of
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Speaker 1: the essential and distinctive features of the art as it
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Speaker 1: stands today, an example of almost unprecedented industrial development, are
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Speaker 1: distinctively American. As Frank J. Sprague pointed, out in his
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Speaker 1: paper before the Electrical Congress of nineteen o four, from
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Speaker 1: which much of the following matter is taken. Brandon Vermont
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Speaker 1: birthplace and Thomas Davenport Blacksmith father are the names first
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Speaker 1: on the genealogical tree of the electric railway in the
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Speaker 1: year eighteen thirty four. A toy motor mounted on wheels
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Speaker 1: propelled on a few feet of circular railway by a
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Speaker 1: primary battery. Exhibited a year later at Springfield and again
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Speaker 1: at Boston, is the infant's photograph. This was only three
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Speaker 1: years after Henry's invention of the motor, following Faraday's discovery
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Speaker 1: ten years earlier that electricity could be used to produce
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Speaker 1: continuous motion. The records of Davenport's career, unearthed by the
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Speaker 1: late Franklin Lennard Pope, show this early inventor a man
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Speaker 1: of genius, deserving a high place in the niche of fame,
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Speaker 1: for in a period of six years he built more
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Speaker 1: than a hundred operative electric motors of various designs, many
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Speaker 1: of which were put into actual service, an achievement taking
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Speaker 1: into account the times, well nigh incredible. For nearly two
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Speaker 1: score years, various inventors handicapped with the limitations of the
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Speaker 1: primary battery and in utter ignorance of the principles of
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Speaker 1: modern dynamo and motor construction, labored with small result. The
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Speaker 1: invention by Paginotti in eighteen sixty one of the continuous
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Speaker 1: current dynamo may properly be said to date all modern
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Speaker 1: electric machines. These were developed in their earliest forms by
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Speaker 1: Graham and Ziemens, Wheatstone and Valley, Farmer and Rowland, Hefna, Altanek,
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Speaker 1: and others, and brought into existence the elements essential to
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Speaker 1: any possible commercial success. Yet, notwithstanding that, the principle of
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Speaker 1: the reversibility of the dynamo electric machine and the transmission
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Speaker 1: of energy to a distance by the use of two
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Speaker 1: similar machines said to have been discovered and described by
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Speaker 1: Paginotti in eighteen sixty seven, the same year in which
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Speaker 1: Professor Farmer described the principle of the modern dynamo in
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Speaker 1: a letter to Henry Wilde, and demonstrated independently at the
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Speaker 1: Vienna Exposition by Fontaine and Gram in eighteen seventy three.
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Speaker 1: Many years more passed before the n importance and availability
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Speaker 1: of this principle were generally recognized. From eighteen fifty to
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Speaker 1: eighteen seventy five is a long period relatively, and yet
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Speaker 1: there seemed to have been practically an entire cessation of
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Speaker 1: experimental electric railway work until in the latter year George F. Green,
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Speaker 1: a poor mechanic of Kalamazoo, Michigan, built a small model
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Speaker 1: motor which was supplied from a battery through an overhead
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Speaker 1: line with track return, and three years later he constructed
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Speaker 1: another model on a larger scale. Green seemed to have
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Speaker 1: realized that a dynamo was essential to success, but he
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Speaker 1: did not know how to make one and did not
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Speaker 1: have the means to buy it. Shortly afterward, in eighteen
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Speaker 1: seventy nine, at the Berlin Exposition, Messrs Ziemanns and Haiersker
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Speaker 1: constructed a short line about a third of a mile
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Speaker 1: in length, which was the beginning of much active work
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Speaker 1: by this firm. The dynamo and motor were of the
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Speaker 1: now well known Seamen's type, and the current was supplied
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Speaker 1: through a central rail with the running rails as a
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Speaker 1: return to a small locomotive on which the motor was
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Speaker 1: carried longitudinally, motion being transmitted through spur and beveled gears
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Speaker 1: to a central shaft from which connection was made to
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Speaker 1: the wheels. The locomotive drew three small cars, having a
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Speaker 1: capacity of about twenty people, and attained the speed of
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Speaker 1: about eight miles an hour, perhaps more than to any other.
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Speaker 1: The credit for the first serious proposal in the United
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Speaker 1: States should be awarded to Field. Curiously enough, patent papers
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Speaker 1: were filed by Field, Siemens, and Edison, all within three
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Speaker 1: months of each other in the spring and summer of
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Speaker 1: eighteen eighty. Priority of invention was finally awarded to Field,
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Speaker 1: he having filed a caveat a year before. He had
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Speaker 1: been actively interested in electric telegraphs, and in an account
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Speaker 1: of his work published some twenty years ago, it is
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Speaker 1: stated that he early constructed two electric motors and had
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Speaker 1: in mind the operation of street cars in San Francisco,
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Speaker 1: but had not been able to do anything in the
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Speaker 1: matter because of a realization that a dynamo must be
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Speaker 1: used instead of a battery. In eighteen seventy seven, while
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Speaker 1: in Europe, he saw some grum machines, and on his
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Speaker 1: return two of them were ordered but not delivered. Later,
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Speaker 1: a dynamo was ordered from Zieman's brothers in London, which
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Speaker 1: was lost, and this was replaced by another, which arrived
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Speaker 1: in the fall of eighteen seventy eight. Meanwhile, two grum
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Speaker 1: machines were placed at his disposal, and shortly afterward an
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Speaker 1: electric elevator was operated. In February eighteen seventy nine, he
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Speaker 1: made plans for an electric railway, the current to be
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Speaker 1: delivered from a stationary source of power through a war
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Speaker 1: fire enclosed in a conduit with rail return, and in
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Speaker 1: eighteen eighty to eighty one he constructed and put in
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Speaker 1: operation an experimental electric locomotive in Stockbridge, Massachusetts, pending the
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Speaker 1: settlement of patent interferences between Edison and Field. The seamen's application,
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Speaker 1: being late, was rejected. The two interests were combined in
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Speaker 1: a corporation known as the Electric Railway Company of the
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Speaker 1: United States, and the first work of the company was
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Speaker 1: the operation of an electric locomotive at the Chicago Railway
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Speaker 1: Exposition in eighteen eighty three. The locomotive, called the Judge
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Speaker 1: after the late Chief Justice Field, ran around the gallery
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Speaker 1: of the main exposition building on a track of about
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Speaker 1: one third of a mile in length. The motor used
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Speaker 1: was a Western dynamo mounted on the car and connected
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Speaker 1: by beveled gear to a shaft from which power was
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Speaker 1: transmitted by belts to one of the wheels. The current
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Speaker 1: was taken from a center rail with track return. A
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Speaker 1: lever operated clutches on the driving shaft, and the speed
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Speaker 1: was varied by resistance. The reversing mechanism consisted of two
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Speaker 1: movable brushholders geared to a disk operated by a lever,
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Speaker 1: each arm carrying a pair of brushes, one of which
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Speaker 1: only could be thrown into circuit at a time to
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Speaker 1: give the proper direction of movement. Meanwhile, several other inventors
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Speaker 1: were getting actively into the field of transmission of power
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Speaker 1: and electric railways. In the summer of eighteen eighty two,
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Speaker 1: doctor Joseph R. Finney operated in Allegheny, Pennsylvania, a car
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Speaker 1: for which current was supplied through an overhead wire, on
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Speaker 1: which traveled a small trolley connected to the car with
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Speaker 1: a flexible cable. And about the same time in England,
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Speaker 1: doctor Fleming Jenkin, following a paper by Messrs Ireton and
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Speaker 1: Perry before the Royal Institution on an Automatic Railway, proposed
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Speaker 1: a scheme of telforage, which was developed by those gentlemen.
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Speaker 1: In the early part of the same year, the writer
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Speaker 1: mister Sprague, then a Midchipman in the United States Navy,
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Speaker 1: who had in eighteen seventy nine and eighteen eighty begun
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Speaker 1: the designing of motors, was ordered on duty at the
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Speaker 1: Crystal Palace Electric Exhibition then being held at Sydenham, England.
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Speaker 1: While in London, he became impressed with a belief in
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Speaker 1: the possibility of operating the underground railway electrically. He first
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Speaker 1: considered the use of maine and working conductors, the latter
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Speaker 1: being carried between the tracks with rail return, but noting
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Speaker 1: the complication of switches on certain sections of the road,
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Speaker 1: conceived the idea of a car moving between two planes,
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Speaker 1: traveling on one and making upper pressure contact with the other,
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Speaker 1: those planes being the terminals of a constant potential system.
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Speaker 1: For practical application, the lower of the two planes was
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Speaker 1: to be replaced by the running track and all switches
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Speaker 1: and sidings, and the upper plane by rigid conductors supported
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Speaker 1: by the roof of the tunnel and following the center
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Speaker 1: lines of all tracks and switches. Contact to be made
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Speaker 1: therewith by a self adjusting device carried on the car
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Speaker 1: roof over the center of the truck and pressed upwards
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Speaker 1: by the springs. In eighteen eighty two, he applied for
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Speaker 1: a patent on the first idea, which was but a
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Speaker 1: variation from that shown in other patents, but the second
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Speaker 1: late dormant for nearly three years because of central station
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Speaker 1: work and the development of the application of stationery motors. Meanwhile,
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Speaker 1: in the United States, Charles J. Fran de Poule, a
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Speaker 1: Belgian by birth and a sculpture by original trade and
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Speaker 1: an indefatigable worker, had become interested in electric manufacture and
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Speaker 1: soon energetically attacked the railway problem. His first railway was
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Speaker 1: a small experimental line constructed in Chicago in the winter
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Speaker 1: of eighteen eighty two to eighty three, the current supplied
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Speaker 1: from an overhead wire. In the fall of eighteen eighty three,
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Speaker 1: a car was also run at the Industrial Exposition at Chicago.
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Speaker 1: A year later, a train pulled by a locomotive and
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Speaker 1: taking current from an underground conduit, was successfully operated at
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Speaker 1: the Toronto Exhibition to carry passengers from the streetcar system,
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Speaker 1: and again in the year following Van der Pool operated
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Speaker 1: another train at the same place, using on this occasion
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Speaker 1: an overhead wire and a weighted arm pressing a contact
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Speaker 1: up against it. Experiments were also carried on by him
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Speaker 1: on the South Bend Railway in the fall of eighteen eight,
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Speaker 1: where several cars were equipped with small motors, and also
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Speaker 1: in Minneapolis, where an electric car took the place of
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Speaker 1: a steam locomotive. Other equipments were operated at the New
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Speaker 1: Orleans Exhibition and at Montgomery, Alabama, where the current was
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Speaker 1: at first taken from a single overhead wire which carried
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Speaker 1: a traveling trolley connected to the car by a flexible conductor.
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Speaker 1: Other equipments were put in operation at Windsor, Ontario, Detroit, Michigan, Appleton, Wisconsin,
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Speaker 1: and Scranton, Pennsylvania. In these several equipments, the motors were
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Speaker 1: placed on the front platforms of the cars and connected
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Speaker 1: to the wheels by belts or chains. The cars were
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Speaker 1: headed in one direction and operated from one end only.
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Speaker 1: In eighteen eighty eight, the Van der Pool Company was
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Speaker 1: absorbed by the Thompson Houston, which had recently entered the
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Speaker 1: raililway field, and Van de Pool continued in its active
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Speaker 1: development until his death in eighteen ninety two. Among the
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Speaker 1: early American workers of this period, none was for a
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Speaker 1: time more prominent than Leo Daft, who, after considerable development
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Speaker 1: in motors for stationary work, took up their application to
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Speaker 1: electric railways, making the first experiments towards the close of
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Speaker 1: eighteen eighty three at his company's works at Greenville, New Jersey,
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Speaker 1: these being sufficiently successful to be repeated in November of
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Speaker 1: that year on the Saratoga and Mount McGregor Road. The
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Speaker 1: locomotive used there was called the Ampere and pulled a
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Speaker 1: full sized car. The motor was mounted on a platform
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Speaker 1: and connected by belts to an intermediate shraft carried between
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Speaker 1: the wheels, from which another set of belts led to
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Speaker 1: pulleys on the driving axles. A center rail and the
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Speaker 1: running rails formed the working conductor. Variation of speed was
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Speaker 1: accomplished by variation of field resistance, this being accentuated by
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Speaker 1: the use of iron instead of copper in some of
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Speaker 1: the coils. In the following year Daft equipped a small
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Speaker 1: car on one of the piers at a New York
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Speaker 1: seaside resort, and a little later another one at the
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Speaker 1: Mechanic Sphare in Boston, the motor for this last being
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Speaker 1: subsequently put on duty at the New Orleans Exposition. In
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Speaker 1: eighteen eighty five, work was begun by the Daft Company
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Speaker 1: on the Hampton branch of the Baltimore Union Passenger Railway Company,
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Speaker 1: where in August of that year operations were begun, at
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Speaker 1: first with two and a year later with two more
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Speaker 1: small electric locomotives, which did not carry passengers themselves but
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Speaker 1: pulled regular street cars. A center and the running rail
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Speaker 1: were used for the normal distribution, but at crossings and
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Speaker 1: overhead conductor was installed and connection made to it by
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Speaker 1: an arm carried on the car and pressed up against it.
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Speaker 1: The driving was by a pinion operated on an internal
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Speaker 1: gear on one of the axles. Daft's most ambitious work
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Speaker 1: followed when a section of the Ninth Avenue elevated Road
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Speaker 1: was equipped for a distance of two miles, on which
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Speaker 1: a series of experiments were carried on during the latter
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Speaker 1: part of eighteen eighty five with a locomotive called the
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Speaker 1: Benjamin Franklin. The motor was mounted on a platform pivoted
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Speaker 1: at one end, and motion was communicated from the armature
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Speaker 1: to the driving wheel through grooved gears held in close contact,
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Speaker 1: partly by the weight of the machine and partly by
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Speaker 1: an adjustable screw device. This locomotive, pulling a train of cars,
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Speaker 1: made several trips, but the experiments were soon suspended. This
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Speaker 1: work was followed by street railway equipments at Los Angeles
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Speaker 1: and dad elsewhere using double overhead wires carrying a trolley carriage. Meanwhile,
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Speaker 1: Bentley and Knight, after some experiments in the yards of
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Speaker 1: the Brush Electric Company at Cleveland in the fall of
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Speaker 1: eighteen eighty three, installed a conduit system in August eighteen
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Speaker 1: eighty four on the tracks of the East Cleveland Horse
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Speaker 1: Railway Company. The equipped section of the road was two
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Speaker 1: miles long. The conduits were of wood laid between the tracks,
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Speaker 1: and two cars were employed, which were each equipped with
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Speaker 1: a motor carried under the car body and transmitting power
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Speaker 1: to the axle by wire cables. These equipments were operated
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Speaker 1: with varying degrees of success during the winter of eighteen
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Speaker 1: eighty four and eighty five, but were abandoned later. This
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Speaker 1: work was followed by a double overhead trolley road at Womsocket,
16:55
Speaker 1: the motors being supplied by the Thompson Houston Company, and
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Speaker 1: later by a combined double trolley and conduit road at Allegheny, Pennsylvania.
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Speaker 1: In eighteen eighty four to eighty five, J. C. Henry
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Speaker 1: installed and operated in Kansas City a railway supplied by
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Speaker 1: two overhead conductors, on each of which traveled a small
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Speaker 1: trolley connected to the car by a flexible cable. The
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Speaker 1: motor was mounted on a frame supported on the car axle,
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Speaker 1: and the power was transmitted through a clutch and a
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Speaker 1: nest of gears, giving five speeds. In the following year
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Speaker 1: a portion of another road was equipped. A number of
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Speaker 1: experiments seemed to have been conducted there, and on some
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Speaker 1: the rails were used as a return. The collectors were
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Speaker 1: of different types, and it is said that, among others,
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Speaker 1: there was one carried on the car. The final selection
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Speaker 1: was a trolley having four wheels disposed in pairs in
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Speaker 1: a horizontal plane, carried by and gripping the sides of
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Speaker 1: the wires. This feature, but using one wire and rail return,
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Speaker 1: characterized a road installed by Henry and San Diego, California,
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Speaker 1: opened in November eighteen eighty seven. Meanwhile, work had begun
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Speaker 1: in Great Britain, where the first regular road to be
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Speaker 1: put in operation was that known as the Portrush Electric Railway.
18:22
Speaker 1: In Ireland, installed in eighteen eighty three by Seamen's Brothers
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Speaker 1: of London, power was generated by turbines and the current
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Speaker 1: was transmitted by a third rail supported on wooden posts
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Speaker 1: alongside of the track, the running rails constituting the return.
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Speaker 1: The pressure used was about two hundred fifty vaults. This
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Speaker 1: was followed in the same year by a successful short
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Speaker 1: road at Brighton, installed by Magnus Folk, the current being
18:51
Speaker 1: transmitted through the running rails. Then came the railway installed
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Speaker 1: at Bessbrook, Newry in eighteen eighty five under the direction
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Speaker 1: of the Messrs Hopkinson, and at Ride in eighteen eighty six,
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Speaker 1: in which latter year was also installed the Blackpool Road
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Speaker 1: by Holroyd Smith. In this latter case, the convoad system
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Speaker 1: was used with complete metallic circuit. The motor was carried
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Speaker 1: underneath the car between the axles and connected by chain gearing.
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Speaker 1: Fixed brushes with and contact were used for both directions
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Speaker 1: of running. Reverting to work in the United States, Sprague
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Speaker 1: again took up the electric railway problem, and in eighteen
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Speaker 1: eighty five before the Society of Arts Boston advocated the
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Speaker 1: equipment of the New York Elevated Railway with motors carried
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Speaker 1: on the trucks of the regular cars, and work was
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Speaker 1: actually begun on the construction of experimental motors. Shortly afterward,
19:51
Speaker 1: a regular truck was equipped and a long series of
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Speaker 1: tests made on a private track in New York City.
19:58
Speaker 1: In May eighteen eighty six, an elevated car was equipped
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Speaker 1: with these motors and a series of tests begun on
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Speaker 1: the thirty fourth Street branch of the road. These motors
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Speaker 1: may be considered the parent models of the modern railway motor.
20:14
Speaker 1: They were centered through the brackets on the driving axles,
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Speaker 1: connected to them by single reduction gears, and the free
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Speaker 1: end of the motor was carried by springs from the
20:24
Speaker 1: transom the truck, elliptics being interposed between this support and
20:28
Speaker 1: the car body. The truck had two motors. They were
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Speaker 1: run open, had one set of brushes, and were used
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Speaker 1: not only for propelling the car but for breaking it.
20:41
Speaker 1: The motors were at first shunt wound, but later had
20:44
Speaker 1: a correcting coil in series, with the armorture at right
20:47
Speaker 1: angles to the normal field to prevent shifting of the
20:51
Speaker 1: neutral point. The car was operated from each end by
20:55
Speaker 1: similar switches. Current at six hundred vaults was used and
21:00
Speaker 1: of speed was effected by cutting out resistance in the
21:03
Speaker 1: armature circuit and then by reducing the field strength. This
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Speaker 1: enabled energy to be returned to the line when decreasing
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Speaker 1: from high speed, it being impossible to interest the railway management,
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Speaker 1: the experiments were finally suspended. Soon afterward, a locomotive designed
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Speaker 1: by Field had a short trial on the same section
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Speaker 1: of the elevated Sprague then turned his attention to building
21:31
Speaker 1: a locomotive car of three hundred horse power capacity, each
21:35
Speaker 1: truck to be equipped with two motors, each having a
21:38
Speaker 1: pair of armatures geared to the axle. But this evidently
21:42
Speaker 1: being ahead of the times, and the possibilities of street
21:46
Speaker 1: tramway traction becoming evident, these equipments were abandoned, and he
21:51
Speaker 1: began the development of the type of motor finally used
21:54
Speaker 1: in Richmond, one crude form of which was first used
21:58
Speaker 1: in storage battery experiments in Philadelphia and others in New
22:02
Speaker 1: York and Boston in eighteen eighty six. Reviewing the conditions
22:08
Speaker 1: at the beginning of eighteen eighty seven, statistics compiled by
22:12
Speaker 1: t Comerford Martin show that, including every kind of equipment,
22:17
Speaker 1: even those a fraction of a mile long and operated
22:20
Speaker 1: in mines, there were but nine installations in Europe, aggregating
22:24
Speaker 1: about twenty miles of track, with a total equipment of
22:28
Speaker 1: fifty two motors and motor cars, none operated with the
22:32
Speaker 1: present overhead line or conduit, and seven cars operated by
22:36
Speaker 1: storage batteries, while in the United States there were only
22:40
Speaker 1: ten installations with an aggregate of less than forty miles
22:44
Speaker 1: of track, and fifty motors and motor cars operated mostly
22:48
Speaker 1: from overhead lines with traveling trolleys flexibly connected to the cars.
22:54
Speaker 1: These were partly daft but principally fanderpool roads. Almost every
22:59
Speaker 1: inn ventor who had taken part in active work was
23:03
Speaker 1: still alive. The roads, however, were limited in character, varied
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Speaker 1: in equipment, and presented nothing sufficient to overcome the prejudices
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Speaker 1: of those interested in transportation and command the confidence of capital.
23:19
Speaker 1: As a result of all these experiments, the series Wound
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Speaker 1: motors soon became universal because of its ability to start
23:26
Speaker 1: a car with the least expenditure of energy, and has
23:30
Speaker 1: held its place to the present time. With minor improvements
23:33
Speaker 1: in its structure and method of gearing. Five hundred fifty
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Speaker 1: to six hundred volts has become standard for the operation
23:40
Speaker 1: of the motors, this value having been found the most satisfactory,
23:45
Speaker 1: Although higher voltages are desirable for economy of transmission. The
23:50
Speaker 1: difficulties encountered in the construction of the motors, offset any
23:54
Speaker 1: advantages gained their bye. As previously explained, the higher the
24:00
Speaker 1: voltage used, the further may the power be economically distributed.
24:05
Speaker 1: In the direct current system, the voltage is limited to
24:08
Speaker 1: about six hundred. With this comparatively low voltage, cars could
24:13
Speaker 1: be economically operated only within a few miles of the
24:16
Speaker 1: generating station. The development of the alternating current transformer, by
24:22
Speaker 1: means of which the voltage could be raised or lowered
24:24
Speaker 1: without mechanism, showed the way to new developments. The direct
24:29
Speaker 1: current generators in the power stations were gradually removed and
24:33
Speaker 1: alternators substituted. Power could be generated at either low or
24:39
Speaker 1: high voltages, stepped up by means of transformers, sent over
24:43
Speaker 1: the line at a high voltage to a substation, dropped
24:47
Speaker 1: to a lower voltage again by the transformers, and changed
24:51
Speaker 1: to direct current by means of rotary converters from which
24:54
Speaker 1: the car lines were fed. This is the system at
24:58
Speaker 1: present in use in all the LAN large cities. The
25:01
Speaker 1: most unsatisfactory part of this system is the substation with
25:05
Speaker 1: its rotary converter, which increases the cost of the substation
25:10
Speaker 1: itself and requires considerable attention. One unfamiliar with the development
25:17
Speaker 1: of motors might ask why the cars were not equipped
25:20
Speaker 1: with alternating current motors. Motors of this class are, however,
25:25
Speaker 1: of quite recent origin, and their application to the severe
25:29
Speaker 1: strains of railway work has only been accomplished in the
25:32
Speaker 1: last four or five years. One of the most successful
25:36
Speaker 1: of these is the alternating current series motor, developed by
25:40
Speaker 1: the Westinghouse Company, and it promises soon to be very
25:44
Speaker 1: widely applied. The outlook for equipping long railway lines heretofore
25:49
Speaker 1: operated by steam is very promising, and in fact has
25:53
Speaker 1: already begun. In May nineteen o five, the Westinghouse Company
25:58
Speaker 1: completed the first heavy locomotive to be operated by single
26:02
Speaker 1: phase alternating current. This locomotive complete weighs one hundred thirty
26:08
Speaker 1: six tons. It was built in two halves, each having
26:12
Speaker 1: three axles. Each axle driven by a two hundred twenty
26:17
Speaker 1: five horse power single phase series motor having single reduction
26:22
Speaker 1: gears with a ratio of eighteen to ninety five. The
26:26
Speaker 1: current required to operate this locomotive, six thousand, six hundred
26:31
Speaker 1: vaults twenty five cycles, is collected from the trolley wire
26:35
Speaker 1: by means of a pneumatically operated pentagraph trolley with sliding
26:40
Speaker 1: contact and carried through an oil switch and circuit breaker
26:44
Speaker 1: to an autotransformer. In this transformer, it is reduced to
26:48
Speaker 1: three hundred twenty five vaults, at which pressure it is
26:52
Speaker 1: used in the motors. This locomotive, being designed for heavy
26:56
Speaker 1: freight service, develops a drawbar pull of five fifty thousand
27:00
Speaker 1: pounds at speed off from ten to twelve miles per hour.
27:06
Speaker 1: Following several other successful applications of these motors, the New York,
27:11
Speaker 1: New Haven and Hartford Railroad decided to equip its roads
27:15
Speaker 1: as far as Stamford, Connecticut, a distance of twenty two miles,
27:20
Speaker 1: with the Westinghouse system. The locomotives used weighs seventy tons
27:25
Speaker 1: and are each equipped with four gearless motors of two
27:28
Speaker 1: hundred fifty horse power each. These locomotives operate over twelve
27:33
Speaker 1: miles of tracks in the city of New York by
27:37
Speaker 1: means of six hundred volts direct current, and over twenty
27:40
Speaker 1: two miles of tracks supplied with alternating current at eleven
27:45
Speaker 1: thousand vaults twenty five cycles. Each locomotive is capable of
27:50
Speaker 1: hauling a two hundred ton passenger train. In accommodation service,
27:55
Speaker 1: requiring one stop every two miles at a scheduled speed
27:59
Speaker 1: of twenty six miles per hour and a maximum speed
28:02
Speaker 1: of forty five miles per hour. In express service, a
28:06
Speaker 1: maximum speed of sixty to seventy miles per hour can
28:09
Speaker 1: be attained. Perhaps the longest line yet equipped is that
28:13
Speaker 1: of the Spokane and Inland Railroad, having a total length
28:17
Speaker 1: of track of one hundred forty six miles. It has
28:23
Speaker 1: been attempted to apply other forms of alternating current motors
28:26
Speaker 1: to railway propulsion. One of these is known as the
28:30
Speaker 1: repulsion motor, and although it has been tried on short lines,
28:34
Speaker 1: it does not as yet appear to have been so
28:37
Speaker 1: successful as their series type. This forum has also been
28:41
Speaker 1: used in Germany, where some interesting tests on high speed
28:45
Speaker 1: lines have been made, during which speeds of one hundred
28:48
Speaker 1: forty miles per hour have been recorded and one hundred
28:51
Speaker 1: twenty six miles per hour with a car carrying passengers.
28:58
Speaker 1: End of section twenty eight